• The Plant Pathology Journal
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• 제33권2호
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• pp.103-108
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• 2017

World wheat production is now under threat due to the wheat blast outbreak in Bangladesh in early March 2016. This is a new disease in this area, indicating the higher possibility of this pathogen spreading throughout the Asia, the world's largest wheat producing area. Occurrence of this disease caused ~3.5% reduction of the total wheat fields in Bangladesh. Its economic effect on the Bangladesh wheat market was little because wheat contributes to 3% of total cereal consumption, among which ~70% have been imported from other countries. However, as a long-term perspective, much greater losses will occur once this disease spreads to other major wheat producing areas of Bangladesh, India, and Pakistan due to the existing favorable condition for the blast pathogen. The wheat blast pathogen belongs to the Magnaporthe oryzae species complex causing blast disease on multiple hosts in the Poaceae family. Phylogenetic analysis revealed that the Bangladesh outbreak strains and the Brazil outbreak strains were the same phylogenetic lineage, suggesting that they might be migrated from Brazil to Bangladesh during the seed import. To protect wheat production of Bangladesh and its neighbors, several measures including rigorous testing of seed health, use of chemicals, crop rotation, reinforcement of quarantine procedures, and increased field monitoring should be implemented. Development of blast resistant wheat varieties should be a long-term solution and combination of different methods with partial resistant lines may suppress this disease for some time.

• 한국식품위생안전성학회지
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• 제15권3호
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• pp.271-276
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• 2000

시중에서 시판되고 있는 발효비지로부터 총 58종의 균주를 분리하였으며, 그 중 starch 첨가 배지에서 투명환을 형성한 10종을 분리하였다. 이 10종의 균주를 정량적으로 amylase활성 측정을 하여 가장 큰 활성을 가진 2종의 균주를 재분리하여 공시 균주로 선정하였다 공시 균주를 동정한 결과 두 균주 모두 Bacillus sp로 동정되었으며, 각각 을 Bacillus sp. GM7330과 Bacillus sp. GM7312라고 명명하였다. 분리된 2종의 균주는 모두 5% 두부비지 용액에 glucose 3%와 yeast extract 0.15%를 첨가하여 초기 pH를 6.0으로 조정하여 30。C에서 72 hr 배양하였을 때 각각 488 units과 341 units_로 가장 큰 활성의 amylase를 생산하였다.

• 한국미생물·생명공학회지
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• 제29권3호
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• pp.134-141
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• 2001

경기도 일대의 가금류 공장부근 토양로부터 단백질 분해활성이 높은 균주를 분리한 후 이것들 가운데 Keratinolytic protease 생산성이 우수한 균주는 KP-364를 선별하여 효소생산을 위한 최적 배양조건을 검토하였다. 선별된 KP-364 는 형태학적 생화학적 특성을 종합한 결과 Pseudomonas sp 로 동정되었으며 편의상 Pseudomonas sp. KP-364로 명명하였다. 효소생산을 위한 최적 배지조성은 Keratin 0.1% glucose 2.0% soybeam meal 0.5% NaNO3 0.5% KCI 0.2%이었고 초기 pH 6.5 배양온도 $37^{\circ}C$, 48시간진탕 배양할때 효소생산이 가장 우수하였으며 이때의 효소의 역가는 1,270 U/ml/hr이었다.

• 한국정밀공학회지
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• 제20권5호
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• pp.156-163
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• 2003

In order to investigate the possibility of punching process of brittle material by ball impact, the effects of sealing materials about impact damage of soda-lime glass by small spheres were evaluated experimentally. The using of sealing materials in the development of perfect cone crack was more effective than no using of sealing materials. At the sealing materials condition, in the case of 5mm-thick specimen, Copper and PMMA sealing were more effective in producing a perfect cone formation than the other sealing materials. And in the case of 8mm-thick specimen, Aluminum sealing was most effective in producing a perfect cone formation. The impact velocity range over which perfect cones were formed was influenced by both the thickness of specimen and sealing materials. By a proper selection of sealing materials, the application fur industrial technology for hole (or nozzle) punching process of brittle materials is expected.

• 한국미생물·생명공학회지
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• 제22권1호
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• pp.92-98
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• 1994

The bacteria which secrete surface-active agent and decrease the surface tension of culture broth were isolated from soil samples. Among them, biosurfactant producing strain KK-7 was selected and emulsification was also detected. The KK-7 produced biosurfactant not only lipid but also glucose by using carbon source. Taxonomical characterization tests have demostrated the strain KK-7 to be Pseudomonas aeruginosa. The media composition of the P. aeruginosa KK-7 for the biosurfactant production was 1% glucose, 0.5% tryptone, 0.2% yeast extract, 0.15% potas sium phosphate mono-dibasic, 0.05% MgSO$_{4}$, initial pH 8.5, at 30$\circ $C for 2 days. In this condition, the concentration of biosurfactant was reached CMC 5 in the culture broth. Surface active material was produced maximum at stationary8 phase, but emulsification power was higher at log phase than stationary phase. It was considered that P. aeruginosa KK-7 produced biosurfactant more than one type having defferent properties and each maximum production time was different. The minimun surface tension of biosurfactant in 50 mM Tris buffer (pH8.0) was 28 dyn/cm, and CMC was 1 g/L.

• 한국미생물·생명공학회지
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• 제22권4호
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• pp.333-339
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• 1994

In order to screen microorganisms producing phospholipase D (PLD) [EC 3.1.4.4], culture broths of about 900 strains of soil bacteria were subjected to examine for the PLD activity. When the hydrolytic activity of PLD (H-activity) in the supernatant was determined, 64 strains produced PLD more than 0.3 unit/ml and all of them were actinomycetes. Among 26 culture broths tested, 6 ones had transphosphatidylation activity (T-activity) of 30~68%. When the strains except one were cultivated on 3 different media at 30$\circ$C for 3 days under aerobic condition, strain # 1090 on medium B (yeast extract 1%, peptone 1%, glucose 1.5%, glycerol 1%, CaCO$_{3}$ 0.4%, and pH 7.2) produced PLD with much higher H- and T-activity, which were 8.3 units/ml and 76.3%, respectively. Subsequently, time course of PLD production of the strain # 1090 during cultivation with aeration of 1 v/v/m and agitation of 400 rpm at 30$\circ$C for 5 days on medium B in jar fermentor was investigated. H-activty of PLD reached almost maximum (about 9 units/ml) after 32 hours and maximal T-activity was found to be about 80%.

• 한국연소학회지
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• 제15권1호
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• pp.30-37
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• 2010

Carbonization characteristics of Indonesian bamboos were investigated using lab-scale tube furnace, in order to find optimum design temperature of a carbonizer for producing bamboo charcoal and vinegar. The bamboo samples used in this study are local bamboos from Damyang in Korea, Andong and Petung in Indonesia. Correlation of electric resistance, specific surface area and pH of bamboo vinegar with pyrolysis temperature has been investigated. Electric resistance of the charcoal increased for higher pyrolysis temperature the specific surface area was also increased as carbonization temperature got higher. Charcoal which has specific surface area of over $300\;m^2/g$ could be produced at $700^{\circ}C$. pH of bamboo vinegar was decreased for highter carbonization temperature and vinegar under pH 3 could be produced for all bamboo samples. In this experimental condition, it was found that lower carbonization temperature is better for producing bamboo vinegar of high quality, while higher temperature is better for obtaining bamboo charcoal with larger surface.

• 천문학회보
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• 제39권2호
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• pp.97.2-97.2
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• 2014

In this paper, we study the stability and dynamics of a magnetic field producing the M6.6 class solar flare taking place in NOAA active region (AR) 11158 on 2011 February 13th. Toriumi et. al. (2013) recently suggest that a fine scale magnetic structure on the photosphere gives a major possibility to produce the M6.6 class flare. On the other hand, they don't discuss the torus instability as a plausible mechanism even though Zhao et. al. (2014) and Janvier et. al. (2014) suspect it as the trigger mechanism of X2.2 class flare taking place later in the same AR. We are the first to investigate the stability of a nonlinear force-free field (NLFFF) prior to the M6.6 class flare against the torus instability by using analytical and numerical approaches. Consequently, we found that our NLFFF is quite stable against small perturbation. This result supports that the flare is triggered by the photospheric motion suggested by Toriumi et. al. (2013). We further perform another MHD simulation with an anomalous resistivity using the NLFFF as an initial condition. As a result, we found the eruption of strongly twisted lines. We compare our simulation results with observations and discuss relevant dynamics in detail.

• 대한치과의사협회지
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• 제53권11호
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• pp.870-885
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• 2015

This article discusses accomplishments and historical implications of American missionary dentist W.J. Scheifley and the first Korean dental department, which was established in 1915 in Korea. W.J. Scheifley, with Christian service mind and mission as a dentist, applied to American Protestantic missionary dentist overseas. The dental department in the Severance Union Medical College introduced the scientistic dental education of America, facilitated research on the dental condition of the Korean people, and ran independent dental clinic. W.J. Schiefley criticised the profit-seeking attitude of Japanese dentists and denturist(="IPCHISA", in Korean pronunciation) and emphasized on the significance of Oral Health. He did all kind of dental treatments with advanced equipments like X-ray machine, and managed the collective oral health care for missionaries overseas. He trained medical students and assistants of the dentists with the goal of producing Korean dentists, but he failed due to the Dentist law introduced by Japanese colonial administration that interfered with producing Korean dentists. However, O.R. Avison's proposal of the establishment of dental schools stimulated the establishment of Kyungsung dental school, which provided the basis for the Dental department in the Severance Union Medical College becoming special training institution for Korean Dentists.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1154-1157
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• 2003

The spent fuel slitting device is an equipment developed for the separation of the pellet and hull from the cutting fuel rod with length of 250 mm, and in order to feed UO$_2$ pellet. We have analyzed on the existing technologies for designing and producing of the slitting device in the first year(2001), based on these results, designed and produced the rod slitting device. It has effectively separated the pellet from the hull, but demanded the supplement separation work because of the mixing with pellet and hull in the vessel, and required the condition for the reducing time of the process. In the second year(2002), we have reduced the work time, performed the test and capacity evaluation with the improving device, based these results, and ensured the data demanded for designing of the spent fuel rod slitting device. We have compared with the DUPIC(Direct use of spent PWR fuel in CAND reactors) process, and developed the device for the purpose of reducing over 40 % in comparition with the DUPIC operation time(5 minutes). Based on these results, it will is effectively applied to available data for designing and producing of the hot test facility.